Process for making curved flanged bars



Patented June 15, 1920.

3 SHEETS-SHEET l.

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MX ATTORNEYS R. s. sMnH. PROCESS FOR MAKING CURVED FLANGED BARS.

j@ l f i, R. S. SMITH. PRocEss Fos MAKING cuRvEn FLANGED BARS.

ILED APR 7.19

APPLICATION F 19.

Patented June 15, 1920.

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1,343,647. Ejfg' Z,

I N V E NTO R P5050/ .snm/fr .s4/mf ATTORNEYS,

R. S. SMITH.

PROCESS FOR MAKING CURVED FLANGED BARS.

APPLICATION man APR.7.1919.

1,343,647. Patnted June 15, 1920.

3 SHEETS-SHEET 3.

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BY @my Meaux,

ATTORNBS` UNITED STATES REUBEN STANLEY SMITH, OF MILNA'UKEE, WISCONSIN.

y PROCSS FOR MAKING CURVED FLANG-ED BARS.

Specification of Letters Patent.

Patented June 15,1920.

Application filed April 7, 1919. Serial No. 288,085.

To all whom, t may concern.'

Be it known that I, RnUnN STANLEY SMITH, a citizen of the United States, residing in the city of Milwaukee, in the county of Milwaukee and State of Visconsin, have invented a certain new and useful Improvement in Processes for Making Curved Flanged Bars, and do hereby declare that the following is `a full, clear,`and exact description thereof, such as will enable persons skilled in the art to which the invention pertains to make, use, and practise the saine, reference being had to the drawings hereto attached for disclosure as to certain details of construction and arrangement of a press by which my 4process may be cai'- ried out.

My invention'relates to improvements in processes ofshaping sheet metal blanks, with particular reference to that class of operations in which the margins of a curved blank are to be bent perpendicularly to the 4 central portion of the blank to form a channel iron frame bar such, for example, as the side bars and cross bars of motor driven vehicle frames.

Heretofore the general practice has been to cut the blank along curved lines from a rectangular strip or sheet of metal and s ubsequently shape the blank 1 n a drawing press by bending the marginal portions thereof at right angles to the central or web portion. This process is not only wasteful when curved blanks are cut from rectangular strips or sheets, but the bending process weakens the bar and develops mechanical difficulties which affect the operaticii of the press, the material composing the marginal flanges` of the bar being stretched on the concave side and compressed-on the convex side,the margins of the blank tending to split or'draw apart on the concave side and `tending to wrinkle, bulge, or thicken on the convex side.

The object of my invention is to provide means whereby a rectangular strip of metal of the required width may be b odily displaced or offset laterally or edgewise to produce the required curve in the blank, this bodily displacement being utilized to partially Jfold the margin of" the blank onv the convex side to produce a flange substantially perpendicularto the web portion of the blank and thereby avoiding stretching this `margin in a mannerto weaken the ange,

.the marginal portion of theflange onf the concave side being simultaneously crimped or corrugated to take up the surplus material and prevent undue crushing stresses or molecular displacement, such as would otherwise tend to thicken this portion of the blank. I then complete the operation in a drawing press by bending the marginal portions of the blank perpendicularly to the central or web portion, the corrugations tending to stretch out in conformity to a continuously concave curved line or cylindrical plane, theI straightening out process i being assisted by the pressure of the opposing walls of the matrix and the plunger. On the opposite side of the blank, the flange along the continuously curved portion willV 'have been substantially completely formed in the central portion of the curve and the remaining marginal portions which enter into the flange will be formed in the drawing press in the usual manner.

My invention also comprises the step `ot' crimping or wrinkling the margin of the blank in the vicinity of the points at which concave flanges are to be formed. This crimping or wrinkling will draw from the material of the plate a length somewhat greater than will be required in forming the flange. The fullness of material thus provided enables the flange to be turned in the drawing press, without unduly straining the `metal, and thus structural weakness is avoided.

In the drawings Figure l is a plan view of a set of press plates employed in carrying out my improved process, with dotted lines indicating the position of the blank and with the top plate partially broken away to show the means for applying pressure to one edge of the plate and to also show the recesses into which the other margin of the plate is turned when the plate `is displaced laterally by pressure applied to the first mentioned edge thereof'.

F ig. 2 isa sectional view drawn on line 2-2 of Fig. l.

v Fig.` 3 is a sectional View drawn on line 3-3 of Fig. 1.

Fig. l is a plan. view of the blank as it appears when removed from the offsetting press. v 'Y Fig. 5 is an edge view of the same as v irwed from the conically curved corrugated sic e.

Figst 6,7, and 8 are sectional views drawn trated by the dotted lines a,

respectively on lines 6 6, 7-7, and 8-8 of Fig. 4.

Fig. 9 is a plan view of the matrix and with dotted lines indicating the position in which the blank is placed upon the matrix.

Fig. 10 Vis a cross-sectional view same drawn on line 10-10 of Fig. 9.

Fig. 11y is a plan view of the completed bar as seen from the sideopposite that from which the flanges project.

Fig. 12 is an end view of the same. Like parts are erence characters throughout the several views.

In carrying out my process, l first prepare a rectangular strip of metal of the desired width and length, such a strip beingillus- Z1,.in Fig. 1. l place this strip ofpmetal upon a bed or platen 1, and subject it to the pressure ofy a moving press plate 2, having a depending shoulder plunger of a drawingpress,

of the at 3 conforming in contour to the desired tion indicated by the arrows in the recess 6.

curvature of the blanken the concave side thereof. The bed or platen 1 is provided with recesses 6 into which the projecting margin of the blank may be turned when the blank is bodily offset by the pressure of shoulder 3 against the opposite edge or margin thereof.

The press plate 2 is provided with radiating corrugations 8, each perpendicular to the Vcurving line of the shoulder 3, in the central portion thereof and extending from the shoulder forwardly from the'blank.

A relative movement of the platen 1 and press plate 2 uponeach Votherin the direcforce the central portion of the blank toward Along the curved margin, the blankwill be allowed to wrinkle, the ma terial being forced into the corrugations 8 of the press platev 2, thereby taking up the surplus stock due to the inwardly swinging movement of the blank on opposite sides of the central line at the apex of shoulder 3.

On the opposite side of the blank, the

`margin will fold sharply into the recess in proportion to `the extent of the bulge produced by the pressure of the shoulder 3 against the opposite side'of the blank. At

the centeror apex of the curve, the bulging marginof the blank will fold or turn and form substantially a right angle to the plane ofthe sheet, as illustrated in Fig. 6. Near the ends of the curve, it will fold into the recess'to a less `extent `as indicated in Fig. 7 which shows a section of the blank drawn on line'7-7 of Fig 4c. The straight end portions of the 'blank will remain 'flat as iiidicated by the sectional view shown in Fig. 8.

Theblank will, therefore, assume the form illustrated in Figs. 4 to 8 inclusive, the concave margin of the curved central portion identiiied by the same ref-- Fig. 2 will f tions 11 and the. opposite margin being folded to produce the iiange 12, the central portion of the blank and also the end portions remaining flat.

The blank is .then placed inV a drawing press as illustrated in Fig. l() with the central portion of the blank supported by a knock-out plate 14, which also serves as a clamping member, whereby the central portion of the blank is held between it and the plunger 15. The central portion of the flange 12bears against the side of the plunger 15 as shown in Fig. 10, whenthe plunger has descended to Vgripping i position preparatory to forcing the blank into the matrix ,cave

ity 16. f p

` It is VVobvious that, if the plunger is actuated in the direction indicated by the arrow in Fig. 10, the plunger will be carried into the matrix cavity .16 andthe side margins will be completely folded alongthesides of the plunger 15 and substantiallyV at right angles to the 'portion which is gripped between the plunger and the plate 1li. The

the corrugations. The Vblank illustrated in the drawings will, therefore, 4assume the formy of a completed channel iron fra-ine bar of substantially the .form las illustrated in Figs. 11 and 12. c Y

The form of the press plates 1V aiid"2,and their arrangement and manner of operation as herein illustrated' is disclosed in a former application, Serial No. 225,791, filed March 30, 1918, by Henry 'Millen and is not herein claimed as a part ofthe present invention.

For the purposes fof the invention herein claimed, any lineans 'for curving .a blank by applying an offsetting pressure to one edge lmargin thereof, while holding the ,side faces in parallel'planesfexcept along the bulging margin of the blank where the latter is per mitted to fold in lone direction, may-be adapted for the purpose of carrying out my process. Y

In crimping or wrinkling the margin of the blank at `points where the curved flanges are to be formed, the stretching'or expansion of the -metal isdistributed over an area which is greater in` a longitudinal direction than the length o'f the arc forming the curve.

Thus, a fullness is provided in the margin of the "blank, by drawing the 4substance thereof from a greater area Vof the blank than is required for the formation of the curved flange. VIn `other words, the strain un the metal is taken up by and evenly dising out the wrinkled portions.

lVhat I claimand desire to secure byLet- A ters Patent is l. The process of shaping sheet metal blanks, consisting in applying a blank bending pressure to one edge of the blank along a conveXly curved line to-concavely bend said edge and offset the blank laterally, si-y multaneously crimping the blank along said curved line to form corrugations vtherein eX- tending perpendicularly to said .line from the edge of the blank inwardly and bending the bulging margin of the blank on the opposite side thereof away from the plane of the sheet in which said pressure is eX-V erted. l

2. The process of shaping sheet metal blanks, consisting in applying a blank bending pressure to one edge of the blank along a convexly curved line to concavely bend said edge and offset the blank laterally, simultaneously crimping the blank along said curved line to form corrugations therein extending perpendicularly to said line from the edge of the blank inwardly, and bending the bulging margin of the blank on the opposite sideJ thereof away from the plane in which said pressure is exerted, and subsequently bending the remaining portions of the side margins' of the blank in the same direction.

3. The process of shaping sheet metal blanks, consisting in applying a blank bending pressure to one edge of the plate along a convexly curved line to concavely bend saidk edge and offset the blank laterally, simultaneously crimping the blank along said curved line to form corrugations therein eX- rtending perpendicularly to said line from the edge of the blank inwardly and bending the bulging margin of the blank on the opposite side thereof away yfrom the plane in which said pressure is exerted, and subsequently bending the other portions of the side margins in the same direction, and subjecting the crimped margins to pressure eX- erted against the bulging portions of the corrugations to flatten them and eliminate the corrugations.

4, The process of shaping sheet metal blanks, consisting in forcingone edge of the blank inwardly along a concavely curving line, corrugating the marginal portion perpendicularly to its inwardly curving edge, and simultaneously holding the flat surfaces of the blank from distortion eX- cept in the direction of said pressure and along the bulging margin opposite that against which said pressure is eXerted, permitting said bulging margin to bend away from the plane in which. said pressure is eX- erted, and along a curvedline substantially parallel to the concavely curving line.

5. The process of forming a curved channel bar, which consists, rst, in imparting the desired outline by offsetting the blank edgewise, simultaneously ,corrugating theV edge of' the blank on the shorter radius and turning the margin on the longer radius away from the plane of the blank, and, second, bending the margins of the blank into the desired angular positions.

6. The process of forming curved channel bars, from sheet metal plates, which consists in simultaneously offsetting the blank edgewise and turning the margin on the longer radius away from the plane ofV the blank, and subsequently bringing the flanges into shape. c

7. The process of making curved flanged bars from sheet metal plates, which consists, first, in oifsetting the blank edgewise and crimping the margin of the plate to provide a fullness at the point where the curved flange is to be formed, and, second, bending the margin of the blank into the desired angular position to form the flange of the bar.

8. The process of making curved flanged bars from sheet metal plates, which consists, first, in offsetting the blank vedgewise and crimping the margin of the plate at points to provide a fullness to avoid subsequent stretching of the metal in producing curved flanges, and, second, bending the margins of the blank into the desired angular positions to form the flange of the bar and simultaneously eliminating the corrugations by pressure.

9. The process of forming curved flanged bars from sheet metal plates, which consists in crimping the margin of the plate Iat points so as to provide a fullness to avoid subsequent stretching of the metal in producing concave flange portions, offsetting the margin from the plane of the plate at other points where convex flange portions are to be produced, and bending the margins of the plate into the desired angular positions to form the flanges of the bar.

l0. The process of formingA curved anged bars from sheet metal plates,`which consists in crimping the margin of the plate at points so as to provide a fullness to avoid subsequent stretching of the metal in producing concave flange portions, offsetting the margin from the plane of the plate at other points where convex flange portions are to be produced, and bending the crimped and offset margins of the plate into the desired angular positions to form the flanges of the bar.

1l. The process of vforming curved chan nel bars, from sheet metal plates, which consists in simultaneously offsetting the blank edgewise and turning the margin on the longer radius away from the plane of the blank and crimping the blank at its concave marginal portion, and subsequently bringing the Hanges into shape.

12. Theprocess of forming curved channel bars, from sheet metal plates, which consists in simultaneously offsetting the blank edgewise and crimping the marginatthe -oilset portions, and subsequentlyV bringing the flanges into shape. Y

13. The process of forming curved chaninelba, from sheet metal plates, which consists in simultaneously offsetting the blank edgewise and crimping the blank at its concave marginal portion, and subsequently bringing the flanges into shape.

of April, 1919. Y

- R. STANLEY SMITH. Witnesses:

W. F. WooLAnD, R. J. MGKERIHAN. 

